pyarrow.fs.HadoopFileSystem

class pyarrow.fs.HadoopFileSystem

Bases: pyarrow._fs.FileSystem

HDFS backed FileSystem implementation

Parameters
  • host (str) – HDFS host to connect to.

  • port (int, default 8020) – HDFS port to connect to.

  • replication (int, default 3) – Number of copies each block will have.

  • buffer_size (int, default 0) – If 0, no buffering will happen otherwise the size of the temporary read and write buffer.

  • default_block_size (int, default None) – None means the default configuration for HDFS, a typical block size is 128 MB.

  • kerb_ticket (string or path, default None) – If not None, the path to the Kerberos ticket cache.

__init__(*args, **kwargs)

Initialize self. See help(type(self)) for accurate signature.

Methods

__init__(*args, **kwargs)

Initialize self.

copy_file

Copy a file.

create_dir

Create a directory and subdirectories.

delete_dir

Delete a directory and its contents, recursively.

delete_dir_contents

Delete a directory’s contents, recursively.

delete_file

Delete a file.

equals

from_uri

Instantiate HadoopFileSystem object from an URI string.

get_file_info

Get info for the given files.

move

Move / rename a file or directory.

normalize_path

Normalize filesystem path.

open_append_stream

Open an output stream for appending.

open_input_file

Open an input file for random access reading.

open_input_stream

Open an input stream for sequential reading.

open_output_stream

Open an output stream for sequential writing.

Attributes

type_name

The filesystem’s type name.

copy_file()

Copy a file.

If the destination exists and is a directory, an error is returned. Otherwise, it is replaced.

Parameters
  • src (str) – The path of the file to be copied from.

  • dest (str) – The destination path where the file is copied to.

create_dir()

Create a directory and subdirectories.

This function succeeds if the directory already exists.

Parameters
  • path (str) – The path of the new directory.

  • recursive (bool, default True) – Create nested directories as well.

delete_dir()

Delete a directory and its contents, recursively.

Parameters

path (str) – The path of the directory to be deleted.

delete_dir_contents()

Delete a directory’s contents, recursively.

Like delete_dir, but doesn’t delete the directory itself.

Parameters
  • path (str) – The path of the directory to be deleted.

  • accept_root_dir (boolean, default False) – Allow deleting the root directory’s contents (if path is empty or “/”)

delete_file()

Delete a file.

Parameters

path (str) – The path of the file to be deleted.

equals()
static from_uri()

Instantiate HadoopFileSystem object from an URI string.

The following two calls are equivalent * HadoopFileSystem.from_uri(‘hdfs://localhost:8020/?user=test’

‘&replication=1’)

  • HadoopFileSystem(‘localhost’, port=8020, user=’test’, replication=1)

Parameters

uri (str) – A string URI describing the connection to HDFS. In order to change the user, replication, buffer_size or default_block_size pass the values as query parts.

Returns

HadoopFileSystem

get_file_info()

Get info for the given files.

Any symlink is automatically dereferenced, recursively. A non-existing or unreachable file returns a FileStat object and has a FileType of value NotFound. An exception indicates a truly exceptional condition (low-level I/O error, etc.).

Parameters

paths_or_selector (FileSelector, path-like or list of path-likes) – Either a selector object, a path-like object or a list of path-like objects. The selector’s base directory will not be part of the results, even if it exists. If it doesn’t exist, use allow_not_found.

Returns

FileInfo or list of FileInfo – Single FileInfo object is returned for a single path, otherwise a list of FileInfo objects is returned.

move()

Move / rename a file or directory.

If the destination exists: - if it is a non-empty directory, an error is returned - otherwise, if it has the same type as the source, it is replaced - otherwise, behavior is unspecified (implementation-dependent).

Parameters
  • src (str) – The path of the file or the directory to be moved.

  • dest (str) – The destination path where the file or directory is moved to.

normalize_path()

Normalize filesystem path.

Parameters

path (str) – The path to normalize

Returns

normalized_path (str) – The normalized path

open_append_stream()

Open an output stream for appending.

If the target doesn’t exist, a new empty file is created.

Parameters
  • path (str) – The source to open for writing.

  • compression (str optional, default 'detect') – The compression algorithm to use for on-the-fly compression. If “detect” and source is a file path, then compression will be chosen based on the file extension. If None, no compression will be applied. Otherwise, a well-known algorithm name must be supplied (e.g. “gzip”).

  • buffer_size (int optional, default None) – If None or 0, no buffering will happen. Otherwise the size of the temporary write buffer.

Returns

stream (NativeFile)

open_input_file()

Open an input file for random access reading.

Parameters

path (str) – The source to open for reading.

Returns

stram (NativeFile)

open_input_stream()

Open an input stream for sequential reading.

Parameters
  • source (str) – The source to open for reading.

  • compression (str optional, default 'detect') – The compression algorithm to use for on-the-fly decompression. If “detect” and source is a file path, then compression will be chosen based on the file extension. If None, no compression will be applied. Otherwise, a well-known algorithm name must be supplied (e.g. “gzip”).

  • buffer_size (int optional, default None) – If None or 0, no buffering will happen. Otherwise the size of the temporary read buffer.

Returns

stream (NativeFile)

open_output_stream()

Open an output stream for sequential writing.

If the target already exists, existing data is truncated.

Parameters
  • path (str) – The source to open for writing.

  • compression (str optional, default 'detect') – The compression algorithm to use for on-the-fly compression. If “detect” and source is a file path, then compression will be chosen based on the file extension. If None, no compression will be applied. Otherwise, a well-known algorithm name must be supplied (e.g. “gzip”).

  • buffer_size (int optional, default None) – If None or 0, no buffering will happen. Otherwise the size of the temporary write buffer.

Returns

stream (NativeFile)

type_name

The filesystem’s type name.